| Comparison with 1859 |
|
genus, by differences not greater than we see between the varieties
of the same species at the present day; and these parent-species, now generally extinct, have in their turn been similarly connected with more ancient species;
and so on backwards, always converging to the common ancestor of each great class. So that the number of intermediate and transitional links, between all living and extinct species, must have been inconceivably great. But assuredly, if this theory be true, such have lived upon
this | this 1859 1860 | | the 1861 1866 1869 1872 |
|
|
On
the
lapse
of
Time
.—
|
Independently of our not finding fossil remains of such infinitely numerous connecting links, it may be objected,
that time will not
have sufficed for so great an amount of organic change, all changes having been effected very
slowly
through natural selection.
It is hardly possible for me even
to recall to the reader,
who may
not be
a practical geologist, the facts leading the mind feebly to comprehend the lapse of time. He who can read Sir Charles Lyell's grand work on the Principles of Geology, which the future historian will recognise as having produced a revolution in natural science, yet
does not admit how incomprehensibly
vast have been the past periods of time, may at once close this volume. Not that it suffices to study the Principles of Geology, or to read special treatises by different observers on separate formations, and to mark how each author attempts to give an inadequate idea of the duration of each formation
or even each
stratum. ↑| 3 blocks not present in 1859 1860 1861 1866; present in 1869 1872 | | We can best gain some idea of past time by knowing the agencies at work, and learning how much of
the surface of the land has been denuded, and how much sediment has been deposited.
As Lyell has well remarked, the extent and thickness of our sedimentary formations are the result and the measure of the denudation which the earth's crust has elsewhere undergone.
Therefore a man should examine for himself the great piles of superimposed strata, and watch the rivulets bringing down mud, and the waves wearing away the sea-cliffs, in order to comprehend something about the duration of past time, the monuments of which we see all around us.
|
|
genus, by differences not greater than we see between the
varieties | varieties 1859 1860 1861 1866 1869 |
| natural and domestic varieties 1872 |
| species; 1859 1860 1861 1866 1869 | | forms; 1872 |
| the 1861 1866 1869 1872 | | this 1859 1860 |
|
On
|
On
1859 1860 1861 | |
On
1866 1869 1872 |
|
the
1859 1860 1861 | |
the
1866 1869 1872 |
|
lapse
1859 1860 1861 | |
Lapse
1866 1869 1872 |
|
of
1859 1860 1861 | |
of
1866 1869 1872 |
|
Time
.—
1859 1860 1861 |
|
Time, as inferred from the rate of Deposition and extent of Denudation
. 1866 |
|
Time, as inferred from the rate of Deposition and extent of Denudation
. 1869 |
|
Time
, as inferred from the rate of Deposition and extent of Denudation
. 1872 |
|
Independently of our not finding fossil remains of such infinitely numerous connecting links, it may be
objected, | objected, 1859 1860 1861 1866 1869 | | objected 1872 |
| will not 1859 1860 1861 1866 | | cannot 1869 1872 |
| very 1859 1860 1861 1866 1869 | very 1872 |
| slowly 1859 1860 1861 1866 | | slowly. 1869 1872 |
| through 1859 1860 1861 1866 | through 1869 1872 |
| natural 1859 1860 1861 1866 | natural 1869 1872 |
| selection. 1859 1860 1861 1866 | selection. 1869 1872 |
| even 1859 1860 1861 1866 1869 | even 1872 |
| reader, 1859 1860 1861 1866 1869 | | reader 1872 |
| may 1859 1860 1861 1866 | | is 1869 1872 |
| be 1859 1860 1861 1866 | be 1869 1872 |
| yet 1859 1860 1861 1866 1869 | | and yet 1872 |
| incomprehensibly 1859 1861 1866 | | incomprehensively 1860 | incomprehensibly 1869 1872 |
| formation 1859 1860 1861 1866 1869 | | formation, 1872 |
| each 1859 1860 1861 1866 | | of each 1869 1872 |
| 3 blocks not present in 1859 1860 1861 1866; present in 1869 1872 | | We can best gain some idea of past time by knowing the agencies at work, and learning how much of
the surface of the land has been denuded, and how much sediment has been deposited.
As Lyell has well remarked, the extent and thickness of our sedimentary formations are the result and the measure of the denudation which the earth's crust has elsewhere undergone.
Therefore a man should examine for himself the great piles of superimposed strata, and watch the rivulets bringing down mud, and the waves wearing away the sea-cliffs, in order to comprehend something about the duration of past time, the monuments of which we see all around us.
|
|
